Rope.



PATENTED MAY 19, 1903;

B. KIRSGH.

ROPE.

APPLICATION IILBD MAR.

F0 MODEL.

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UNITED STATES Patented May 19, 1903.

PATENT OFFICE.

BERIHARD KIRSCII, OF VIENNA, AUSTRIA-HUNGARY, ASSIGNOR OF ONE- HALF TOADOLF PESSL, OF VIENNA, AUSTRIA-HUNGARY.

ROPE.

SPECIFICATION forming part of Letters Patent No. 728,399,'dated May 19,1903.

Application filed March 1 8, 1 8 9 8.

To (0 whom, it may concern.-

Be it known that I, BERNHARD KIRsoH; a subject of the Emperor ofAustria-Hungary, residing at Vienna, in the Province of Lower Austria,in the Empire of Austria-Hungary, have invented certain new and usefulImprovements in Ropes; and I do hereby declare the following to be afull, clear, and exact description of the invention, such as Will enableothers skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, and to lettersof reference marked thereon, which form a part of this specification.

It has been proposed to manufacture ropes by laying upon a central coresuccessive cylindrical layers of yarns, all applied with a certaindegree of tension, in order, on the one hand, to obtain a more equaldistribution of the strain applied by a load throughout the fibers thancan be eifected in ropes of ordinary manufacture,where bytwistingtogether a bundle of yarns the inner yarns are practically notsubjected to any strain when the rope is loaded, and are consequentlyuseless. On the other hand, by the said manufacture of ropes ofcylindrical layers of yarns the further advantage is obtained ofavoiding the production of interstices, such as occur in ordinary ropescomposed of a number of ,twisted strands,and consequently such a rope,

(shown and described in my British patent, No. 24,276, of December 13,1894,) while containing the same amount of fiber, is both stronger andof a less diameter than the ordinary rope.

My present invention has for itsobject to still further increase thestrength of such ropes by not only insuring that a certain strain shallbe put upon each yarn of which the rope is composed, as was heretoforedone, but so arranging the yarns in the several layers that anabsolutely equal strain shall be put upon everyindividnal yarn ofeachlayer when the rope is loaded, and I effect this by laying each yarn ofeach layer with exactly the same angle of twist, and consequently withexactly the same length in a unit of length of the rope.

In the arrangements heretofore proposed Serial No. 874,321. (No model.)

for the manufacture of such ropes it was proposed to lay all the yarnsin such manner that the helical lines formed-thereby should all be ofthe same pitch. By this arrangement the result would be obtained asshown in the diagram Figures 1 and 2 of the accompanying drawings,where,in Fig. 1, ais the helical line formed by a yarn laid upon a cylindricalsurface of the small diameter (Z with the pitch tn, while A is thehelical line formed by a yarn upon a cylindrical surface of the largerdiameter D, also with the same pitch on. Now it will be seen, in thefirst place, that theyarnA has a considerably greater length in thedistance of the pitch 00 than the length of the yarn a, so that onapplying a strain to A it will be capable of stretching to acorrespondingly greater extent than the yarn a when this is subject tostrain, and, secondly, if the yarns A and a be subject to thesamedownward strain in the direction W, then, as the angle a, formed bythe yarn A with the vertical W, is much greater than the angle a, formedby the yarn a, it follows that a much smaller proportion of the verticalstrain W will be transmitted as a longitudinal strain to A than theproportion that will be transmitted to a, so-that although by thisconstruction it is insured that all the yarns in all the layers shall besubject to a certain strain, yet these strains will be very unequal bothon account of the different angles of twist and the difierent degree ofstretching in a unit of length of the rope.

If, on the other hand, all the yarns of the different layers be laidwith precisely the same angle of twist according to my presentinvention, it will be seen that, first, all the yarns contained in aunit of length of rope will be of exactly the same length, a'nd willconsequently be stretched to the same extent on go being subject tostrain, and, secondly, as they will all form an equal angle with thevertieal they will all be subject to the same proportion of the verticalstrain. Thusif the line A, Fig.

3, represent part of a helical yarn laid around 5 a cylinder ofinfinitely large diameter at an angle of twist or, and a, Fig. 4,represent part of a helical yarn laid around the cylinder of thediameterd withthe same angle of twist a,

it will be evident that in the length x of each [00 cylinder the lines Aand a, will be of exactly the same length and will make the same an--gle a with the vertical-W.-

Fig. 5 shows a length'of. roge constructed according tomy'above-des'c'rihed invention, in which at the several superposedlayers A B O D the yarns a b c d are ali laid with the same angle oftwist and are consequently all of the same length in a length m of therope and form the same angle a with the vertical vline of strain W.

7 As usual in this description of rope, the lay in the concentric layersof yarns is left and right hand alternately, or vice versa, in order toavoid the tendency to untwist or kink.

I I claim- 1 1. A rope composed of a core and concentric layers ofhelically-laid yarns, each yarn in all said layers having the same angleof twist and consequentlydiflferent pitch, whereby all the yarns will beequally loaded, sub

stantially as and forthe purpose set forth.

2. A rope, composed of a core and concentric layers of helieally-laidyarns, each yarn of all the layers haying the same angle of BERNHARDKIRSCH.

Witnesses:

HENRY C. CARPENTER, CHAS. E. CARPENTER.

